In recent decades, scientists have learned that chimpanzees can use plants to treat their intestinal parasites, as can elephants, sheep, goats and porcupines. “And even more interesting than that is the fact that recent discoveries are telling us that insects and other little animals with smaller brains can use medication, too,” says de Roode.

For the past 10 years, de Roode has studied monarch butterflies and how they get sick from parasites. He discovered that female monarch butterflies are able to use medicinal milkweed plants to reduce the harmful effects of the parasites on the butterflies' offspring.

“This is an important discovery, I think, not just because it tells us something cool about nature, but also because it may tell us something more about how we should find drugs,” de Roode says. “Most of our drugs derive from natural products, often from plants. In indigenous cultures, traditional healers often look at animals to find new drugs. In this way, elephants have told people how to treat stomach upset and porcupines have told people how to treat bloody diarrhea. Maybe one day we will be treating people with drugs that were first discovered by butterflies. And I think that is an amazing opportunity worth pursuing.”

De Roode is one of the featured speakers for the 2015 Darwin Day Dinner in Atlanta on Sunday, February 15. The title of his talk is "How Darwin laid the groundwork for understanding infectious disease." Tickets for the event, sponsored by Atlanta Science Tavern, sold out within days after they came available a few weeks ago.